近日在做一些OA前端界面，为了更好管理页面代码想写个js选择器，写着写着发现很费力，索性在网上找找看，功夫不负有心人， 找到一个mini css选择器，且性能不凡：以下代码是压缩后的，仅2KB。
代码如下:
var $=(function(){var b=/(?:[/w/-//.#]+)+(?:/[/w+?=([/'"])?(?:///1|.)+?/1/])?|/*|>/ig,g=/^(?:[/w/-_]+)?/.([/w/-_]+)/,f=/^(?:[/w/-_]+)?#([/w/-_]+)/,j=/^([/w/*/-_]+)/,h=[null,null];function d(o,m){m=m||document;var k=/^[/w/-_#]+$/.test(o);if(!k&&m.querySelectorAll){return c(m.querySelectorAll(o))}if(o.indexOf(",")>-1){var v=o.split(/,/g),t=[],s=0,r=v.length;for(;s<r;++s){t=t.concat(d(v[s],m))}return e(t)}var p=o.match(b),n=p.pop(),l=(n.match(f)||h)[1],u=!l&&(n.match(g)||h)[1],w=!l&&(n.match(j)||h)[1],q;if(u&&!w&&m.getElementsByClassName){q=c(m.getElementsByClassName(u))}else{q=!l&&c(m.getElementsByTagName(w||"*"));if(u){q=i(q,"className",RegExp("(^|//s)"+u+"(//s|$)"))}if(l){var x=m.getElementById(l);return x?[x]:[]}}return p[0]&&q[0]?a(p,q):q}function c(o){try{return Array.prototype.slice.call(o)}catch(n){var l=[],m=0,k=o.length;for(;m<k;++m){l[m]=o[m]}return l}}function a(w,p,n){var q=w.pop();if(q===">"){return a(w,p,true)}var s=[],k=-1,l=(q.match(f)||h)[1],t=!l&&(q.match(g)||h)[1],v=!l&&(q.match(j)||h)[1],u=-1,m,x,o;v=v&&v.toLowerCase();while((m=p[++u])){x=m.parentNode;do{o=!v||v==="*"||v===x.nodeName.toLowerCase();o=o&&(!l||x.id===l);o=o&&(!t||RegExp("(^|//s)"+t+"(//s|$)").test(x.className));if(n||o){break}}while((x=x.parentNode));if(o){s[++k]=m}}return w[0]&&s[0]?a(w,s):s}var e=(function(){var k=+new Date();var l=(function(){var m=1;return function(p){var o=p[k],n=m++;if(!o){p[k]=n;return true}return false}})();return function(m){var s=m.length,n=[],q=-1,o=0,p;for(;o<s;++o){p=m[o];if(l(p)){n[++q]=p}}k+=1;return n}})();function i(q,k,p){var m=-1,o,n=-1,l=[];while((o=q[++m])){if(p.test(o[k])){l[++n]=o}}return l}return d})();
把原版也分享下：
代码如下:
/**
* "mini" Selector Engine
* Copyright (c) 2009 James Padolsey
* -------------------------------------------------------
* Dual licensed under the MIT and GPL licenses.
* - http://www.opensource.org/licenses/mit-license.php
* - http://www.gnu.org/copyleft/gpl.html
* -------------------------------------------------------
* Version: 0.01 (BETA)
*/
var mini = (function(){
var snack = /(?:[/w/-//.#]+)+(?:/[/w+?=([/'"])?(?:///1|.)+?/1/])?|/*|>/ig,
exprClassName = /^(?:[/w/-_]+)?/.([/w/-_]+)/,
exprId = /^(?:[/w/-_]+)?#([/w/-_]+)/,
exprNodeName = /^([/w/*/-_]+)/,
na = [null,null];
function _find(selector, context) {
/**
* This is what you call via x() 这是你们所谓的经x
* Starts everything off... 开始上所有的
*/
context = context || document;
var simple = /^[/w/-_#]+$/.test(selector);
if (!simple && context.querySelectorAll) {
return realArray(context.querySelectorAll(selector));
}
if (selector.indexOf(',') > -1) {
var split = selector.split(/,/g), ret = [], sIndex = 0, len = split.length;
